Cold hardiness & minimum temperature

Is Wild Ginger (Asarum canadense)cold hardy? Hardiness zone & min temp

Also called Wild ginger, Canadian wild ginger, Canada snakeroot.

More about wild ginger

About Wild Ginger

Asarum canadense · also called Wild ginger, Canadian wild ginger · herb

Wild ginger is a low-growing, deciduous native groundcover found in rich, moist deciduous woodlands throughout eastern North America, prized for its large, heart-shaped velvety leaves that form a dense weed-suppressing mat in shaded gardens. Its unusual jug-shaped, maroon-brown flowers are produced at soil level in early spring and are often hidden beneath the foliage. The rhizomes have a ginger-like aroma and have been used medicinally and as a spice substitute, though they contain aristolochic acid, a compound flagged by the FDA as potentially nephrotoxic and carcinogenic with regular consumption. Wild ginger is classified as mildly-toxic to pets due to the presence of aristolochic acid.

Cold limit: USDA 3-7 · RHS H7 (-35–27°C)

What wild ginger's hardiness rating actually means

Yes — wild ginger is genuinely cold hardy. Rated RHS H7 and USDA 3-7, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H7 means: Hardy in the severest European continental winters. On the US scale that maps to USDA 3-7 — the zones where it can be left outdoors year-round.

New to these scales? The USDA hardiness zone map explained covers how the zone numbers work, and you can find your own zone with the zone finder.

Minimum temperature — and what happens below it

Minimum survivable temperature is roughly below about −20 °C. Wild Ginger is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for wild ginger as it gets too cold:

It tolerates winter lows to about −20 °C once established.
Below its rated zone, the visible damage is browned or blackened top growth and, in the worst case, a killed crown or root.
First-year, newly planted, or container-grown specimens are noticeably less hardy than established garden plants — the roots are exposed.

Can wild ginger go outside or overwinter — and where?

Plant it out within USDA 3-7 and it overwinters with little or no help.
It does not want to come indoors — a warm winter room actually weakens a hardy plant by denying it dormancy.
The real risks in its range are waterlogging, wind-rock on young plants, and a late hard frost on new growth — not ordinary winter cold.

Work back from your local frost dates with the frost-date calculator: the last spring frost and first autumn frost are what really decide when wild ginger can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Wild Ginger hardiness — frequently asked questions

Is wild ginger cold hardy?

Yes — wild ginger is genuinely cold hardy. Rated RHS H7 and USDA 3-7, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Wild Ginger is hardy across USDA 3-7; it belongs in the ground or a frost-proof container, not on a windowsill, and many types actively need a cold winter to perform.

What is the minimum temperature wild ginger can survive?

Minimum survivable temperature is roughly below about −20 °C. Wild Ginger is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is wild ginger?

Wild Ginger is rated USDA 3-7 and RHS H7 — Hardy in the severest European continental winters.

Can wild ginger survive winter outside?

Plant it out within USDA 3-7 and it overwinters with little or no help. It does not want to come indoors — a warm winter room actually weakens a hardy plant by denying it dormancy. The real risks in its range are waterlogging, wind-rock on young plants, and a late hard frost on new growth — not ordinary winter cold.

What happens to wild ginger below its minimum temperature?

It tolerates winter lows to about −20 °C once established. Below its rated zone, the visible damage is browned or blackened top growth and, in the worst case, a killed crown or root. First-year, newly planted, or container-grown specimens are noticeably less hardy than established garden plants — the roots are exposed.